1. Field of the Invention
The present invention relates to load control systems for controlling the amount of power delivered to one or more electrical loads and, specifically, to a method of automatically programming a new load control device, such as an electronic dimming ballast, using a remote identification tag, such as a radio-frequency identification (RFID) transponder that is associated with the location (e.g., fixture) in which the new load control device is installed.
2. Description of the Related Art
A typical prior art load control system is operable to control the amount of power delivered to an electrical load, such as a lighting load or a motor load, from an alternating-current (AC) power source. A lighting control system generally comprises a plurality of control devices coupled to a communication link to allow for communication between the control devices. The control devices of a typical lighting control system include lighting control devices (e.g., dimmer circuits or electronic dimming ballasts) operable to control the amount of power delivered to the lighting loads (and thus, the intensity of the lighting loads) in response to digital messages received via the communication link. In addition, the control devices of a typical lighting control system often include one or more keypad devices that transmit commands via the communication link in order to control the loads coupled to the lighting control devices.
Lighting control systems for fluorescent lamps typically comprise a controller and a plurality of electronic dimming ballasts that are operable to communicate via a digital communication link. The controller may communicate with the ballasts using, for example, the industry-standard Digital Addressable Lighting Interface (DALI) communication protocol. The DALI protocol allows each ballast in the lighting control system to be assigned a unique digital address, to be programmed with configuration information (e.g., preset lighting intensities), and to control a fluorescent lamp in response to commands transmitted via the communication link. Some controllers may provide a user interface that allows for control of the lighting control system. The controllers of a lighting control system may comprise, for example, wall-mounted keypads or handheld devices, such as infrared (IR) remote controls, personal digital assistants (PDA). The IR commands are received by an IR receiving sensor that is operable to send appropriate commands to the controlled ballasts. In addition to IR receiving sensors, the lighting control system may also include daylight sensors or occupancy sensors. The daylight and occupancy sensors are operable to monitor the condition (e.g., the ambient light level or motion from an occupant, respectively) of a space and send appropriate commands to the controlled ballasts in response to the sensed conditions in the space.
When the multi-ballast lighting control system is initially installed, each ballast must be configured appropriately. For example, a ballast may be configured to be included in a particular group with other ballasts that are responsive to commands received from a particular IR receiver. That ballast may also be configured to be included in another particular group of ballasts that are responsive to commands received from a particular daylight sensor, or an additional group of ballasts responsive to a particular occupancy sensor. All ballasts within a particular group are operable to be controlled together. In addition, the ballast may be further configured with certain individual operating parameters, such as minimum and maximum light intensity parameters. In order to maintain these configurations, one of the controllers of the multi-ballast lighting control system (e.g., a central processor) is operable to store and update these configurations as needed.
In the event that an existing ballast within the control system fails, the failed ballast must be replaced with a new ballast. The configurations that were associated with the failed ballast must then be reassigned to the new replacement ballast such that the new ballast will operate in the same fashion as the failed ballast had operated. For example, if the failed ballast had been configured to operate in a particular group of ballasts responsive to an occupancy sensor, then the new ballast, once installed in the same location as the failed ballast, must also be configured to operate in the same ballast group responsive to the occupancy sensor.
One prior art method of reconfiguring a new replacement ballast comprises using a hand-held PDA to run a ballast replacement program in which the user enters the unique serial number of the failed ballast and the unique serial number of the new replacement ballast. The PDA can transmit these serial numbers to an IR receiver within the lighting control system. Once these serial numbers are received by the central processor via the communication link, the central processor can update the configurations accordingly such that the new ballast will operate in the same groups and with the same individual operating parameters as the failed ballast. This prior method of reconfiguration is described in greater detail in commonly-assigned U.S. Pat. No. 7,391,297, issued Jun. 24, 2008, entitled HANDHELD PROGRAMMING FOR A LIGHTING CONTROL SYSTEM, the entire disclosure of which is hereby incorporated by reference.
The prior art method of reconfiguration can be tedious as the user must input the serial numbers of both the failed and new ballasts. If many ballasts are to be replaced in the lighting control system, the prior art method becomes even more tedious as more serial numbers must be entered. Thus, there exists a need for a method of automatic ballast replacement and reconfiguration that does not require the user to completely re-program a new ballast or to enter any serial numbers.